Swab



M. M. KENLEY Nov. 12, 1940.

4 SWAB Filed March 29, 1957 wrm Patented Nov, 12, 1940 UNITED STATESPATENT OFFICE Claims.

My invention relates to swabs such as are employed in deep well work inlifting liquids from wells. Such devices are normally employed in wellcasing or in well tubingv to raise comparatively large loads of liquidabove the swab at each trip into the well.

It is an object of this invention to provide a swab having a freeopening therethrough for passage of liquid when the device is loweredinto the well, but which is adapted to securely seal with the pipe whensaid swab is moved upwardly with its load of liquid.

It is another object toprovide a swab with a plurality of sealingrubbers thereon, one of which is slidable on the supporting mandrel toopen or close the passage through said mandrel.

I also aim to construct a particularly effective form of swab rubberwhichwill be strong and durable and yet which will seal closely with thepipe in which it is operated.

The device also includes an effective unloading valve acting to relievethe swab of any excess of liquidlover the amount which it is safe tolift.

In the drawing herewith Fig. 1 is a central longitudinal section througha swab employing my invention.

Fig. 2 is a similar view showing the swab in elevation.

Fig. 3 is a transverse section on the plane 3-3 of Fig. 1 shown somewhatenlarged.

In the drawing my swab is shown as used within a pipe 5 which may be thewell casing. The swab includes a tubular mandrel 6, at the upper end ofwhich is secured a collar or cage 'I having openings 8 therein to permitpassage of fluid. The upper end of the collar is formed with a threadedshank 9 for attachment to a line or cable by means of the socket III.

Spaced downwardly from the collar 'I is a coupling II which forms asupport for the upper swab member. Said swab member includes a lower cupI2 which has an inner collar or thimble I3 tting closely upon saidmandrel and having outer threads or corrugations to frictionally engagewithin the downwardly tapered lower end (Cl. 10S-225) member including acollar I8 and a downwardly flaring skirt I9 fitting closely along theupper tapered end of the rubber. It will be seen that this swab memberhas `only its intermediate eri-1` larged area I1 in contact with thepipe butfthis area may be under compression in the pipe and forms aliuid seal therewith due to lthe load of uid pressing on the surface I5.

Below the upper swab member the mandrel is formed with a large openingfor the entrance of Aliquid to the mandrel. At the lower end of saidmandrel is secured a valve cage 2I having therein a valve 22 heldupwardly into its seat to close the lower end oi the mandrel by acompresi.

sion spring 23. Said spring is supported upon a longitudinallyadjustable' plug 24 which may be locked against unscrewing by atransverse locking pin 25. The spring is adjusted to hold said valveclosed with a predetermined pressure. When the load of liquid above theswab is in excess of a suitable amount, the valve will unseat to allowthe excess to leak past the same. A lateral opening 26 permits escape ofsuch fluid.

Between the cage 2I and the collar II is a second swab rubber l5a of thesame construction as rubber I5, but it is slidable `on the mandrelbetween the said collar and cage and from a position above the opening20 to a position below the same, or vice versa, depending upon thedirection of movement of the swab mandrel.

In the operation of this device it is assembled as shown in the drawingand lowered downwardly into the well and into the liquid standing in thecasing until it assumes a position submerged in the liquid a properdistance to provide a load above the swab such as is safe to lift as oneload. If, for example, the swab is intended to lift four barrels ofliquid atV one time it will be submerged so as to obtain such a loadabove the swab. If by chance the load above the swab is in excess of theamount which is desired the valve 22 is arranged to unseat against thepressure of the spring 23 to allow the excess to pass out the lower end.

It will be seen that as the swab is lowered the swab member I5a will beforced upwardly along the mandrel to the position shown in Fig. l. Therewill, therefore, be a large opening at 20 through which the liquid frombelow the swab may pass upwardly as the swab is lowered. When the propersubmergence is obtained the device will be pulled upwardly and as themandrel is thus moved the lower swab member I5a will slide backwardlyalong the mandrel to the position shown in Fig. 2 below the openings 20.The fluid above the swab will thereby be entrapped within y may beoperated rapidly.

the casing above the swab and will be brought upwardly to the surface bythe movement of the swab. y

An advantage in `this construction is that it is of simple andeconomical construction and As it is dropped downwardly through theliquid the liquid below the swab has` a` free open passage through themandrel while the swab is being lowered. Its passage through the liquidwill therefore be comparatively rapid. When the device is pulledupwardly, however, this opening will be shut off so that the fluid abovewill be entrapped so as to be carried upwardly with the swab.y Theprovision of the unloading valve 22; provides against any overload ofliquid above the swab and in its. construction is exceedingly simple andeasily adjusted.

The particular construction of the swab rubber is extremely eiiective.It has soft rubber adjacent the lower end and is welll reenforced by thecup I2, while at the upper end it is of hard rubber which will not beundulydistorted 2.5- by the load of liquid above and will tend tomainlbe a tendency for the rubber to expand and maintain a proper sealwith the pipe. The threaded or ribbed area I3 tends to frictionallyretain the rubber yet it may be easily replaced.

What is claimed as new is:

1. A swab for wells including a tubular mandrel, upper and lower outletsin said mandrel, a valve in said lower outlet adapted to open underapredetermined pressure from above, a packing rubber fixed adjacent theupper end of said mandrel, an openingin saidrnandrel below said rubber,and a second swab rubber slidable onv said mandrel to positions above orbelow said opening and adapted to form a seal with the outer surface ofthe mandrel.

2. A swab for wells including a tubular mandrel, upper and lower outletsin said mandrel, means normally closing the lower outlet in saidmandrel, a packing rubber fixed adjacent the upper end of said mandrel,an opening in said mandrel below said rubber, and a second swab rubberslidable on said mandrel topositions above or below said opening.

3. A swab for wells. adapted to t within a pipe in the well including, atubular mandrel, a valve normally closing the lower end thereof, butadaptedto unseat under a predetermined pressure downwardly within themandrel, a sealing member iixed to the mandrel and adapted to sealbetween said mandrel and said pipe adjacent the vupper end of saidmandrel, an opening in said mandrel below said member, and meanscomprising a lower sealing member to close the passage of fluid betweensaid mandrel and said pipe below said opening responsive to alongitudinal movement of said mandrel in said pipe, said means beingslidable on said mandrel.

4. A swab for wells adapted to iit within a pipe in the well including,`a tubular mandrel, an overload relief Valve normally closing the lowerend thereof, a sealing member formed to seal between said mandrel andsaid pipe adjasealing member slidable on the mandrel to close thepassage of uid between said mandrel and said pipe `below said openingresponsive to a longitudinal movement of said mandrel in said pipe.

drel having an outlet adjacent its upper end, a .packing rubber fixedupon the mandrel below said outlet, an opening in the mandrel below saidpacking rubber, and a second swab rubber slidable on the mandrel topositions above and below said opening and adapted to form a sealbetween the mandrel and a surrounding pipe.

- MYRON M. KINLEY.

5. A swab for wells including a tubular man-

